Process of regulating internal-combustion engines



3 SheetswSheeu March Z3 9 @2%. 4

A. 2. ATTENDU PROCESS OF' REGULATING INTERNAL COMBUSTON ENGINES FiledDeo. 2V,

March 23 .1926, 1,577,551

A. c. ATTENDU.

PROCESS OF REGULATING INTERNAL COMBUSTIONl ENGINES 5 Sheets--Sheet 2Filed Dec. 27, 1921 llnltllll ZC/Gt Mamh 23 3926.,

A. C. ATTENU PROCESS OF REGULATING TNTERNAL COMBUSTION ENGINES FiledDec. 27, 1921 s sneetshee'g@ am i www Cri if l il@ I in i .ma

lie it known that l. ,"-ixnlu- (l. li'r'ri-:t-inU, n citizen of thellepnhliirul France., und resident (if the elle oi" li'lentrenh in thePreviuie, ol liuehee und lhnniniou el (lnnzulu, hure inveni'eil eertninnew und useful inprovenunils in lroeeses ol' llen'ulntiinollniernnlon'ihusiien Engines, o2.: which 'the il'ollen'ii'n; is n lull,Clear.) unil exact ileseiip tion.

lhis invention teint-es lo Diesel sind like eingines and to uniinpinreil method of Opeeatingi nue-h. ly ,Diesel endl like enginefs isnienul intel-nul eonihueelnn eugineei in which (hiring nei'ninlwerking); the. i'nel is ignited hv leinperniure anni pri-insuresdeveloped upon eonilnessien.

"The ohjeet ot the ini'eutnin is to in'iprore, the liexihilil'y nmleliicieney l" milking; el' sueh engines in.' eimhling eiiproxiinntelyeenzllzini'. preignition preesue nil teni-peinture le lie :illninefiupon eenipression tol' ull en* gine ,L'peeiliia ily :lill nl theinvenion fhe whirling* of :in engine in iineilsilnteil "Clarli'ifeixi'iivii fenipriaee :in iiuiiroretiliewl in' like rngigire er :inie'hoil el' opernt 'h wherein e uorhingj `.".'l1nler pro- .\i h :irhiirgii, el nir :ivnilnhle loi' en1pie:\.im| n.hifxh :ippmxin'nzielylillx lie evliufh-r :it ull engine speeiin nml .rhieh is nl' 1i.pinniiiy hfif is verieil in nueh n nmnuer hnl' :is lim Speeil el lheengine incl-enses the ipiunliiy ilerrenier; nini Jn-e versn 'whereby :innpproxinnileiv romnnt preiggniion prensure nnil lenipe" :inrinin): hezitlnineil upon roinpr .i Mr nll engine speeds.

'the imenlion lan'ner nonnliriseann.iui pi'oi'eil liesei or like engineor 1. method of opel-eline' sui-h wherein .i noi-hing eyliinlei.' iSprovide-eil with :i i-iinigpze olf nir nvnilihle 'for eonnxn'essiinnwhich approximately (ills lhe cylinder nl' :ill engine speeds :nul thequnnlity ol nir'n\'uil.:iiile ler conipresnien iu n workinlgr eylinileris controlled in mnh :t

nmnner that :is the. pe-eil of She engine. increases the quantity el henir is. ileerenell :unl `vice versie hy providing fior the eninpe nl'eonli'ollehle quantities ol' the nir `ironi n, worh'ingg" '."fflinllervfl'ierehji nu npplexnialelv roniunnt preigxnilien .'nermire nmlen'ipelnliu'e nini' he nitnined upon eefnpre-Li- Sien i'pr ull engineSpeeii.

The escape o lnii: freni the ei'liinier inf sureS 'the eliiei-ni:stux'venging; nl' the engine to eliminate burnt ges.

E Bllif, CNADA. ASSIGNOR TO ATTENDU EN- f7, CANADA., A CORPORATION O1?CANADA.

Sex'el No. 524,987'.

IThe Diesel principle, :is is well lmewn, the compression of n Charge ofnir to e point. where he temperature and pressureeendh tiene are suchthat fuel will ignite Sponnneously. At the present tiine,.thiu prlneiple is put in prnetine in such n manner that; n suhstnnl'inllylixeilvoluine olf nir is teken inte 'the engine eylini'ler nl, eneh Stii'ine7regarilless el tl e Speed or temperature of the engine. VJhen theengine. is' runningY at low speed end the eonii'n'essien et this elmejeis eli'eeletl apparently slowly, the nir l'i'ietiou is niueh less thanwhen -epernted nt high Speed, with the result that the ten'iperntnrelees not rise as high with low speellkeenn pression :is with high speedcompression. lhn'hei'niore, with low speed comin-essieu iuore time isgiven for. heut less throieh 1the rylimler wells and in addition 'tothis the less frequent explosions of low speed ninin tnin n Coolercylinder Well. All ihese fue tors eonihine to keep the ten'iperntui'e'from mounting' 'when un engine is running;` nl; inw speed und. :is thepressure obtained is (lependent to a certain extent en i'he'temperntnre,it, 'follows that the pressures when operating :it low speed are ninehlower than the pressures ohtnined when Iepei'nting' :it high speed. ,itfollows, theiefoiey that ".vhen operating` nl', low speed, e ueh.sniniler' quantity ol fuel cnn he burned than when iiipernling nl highspeed, with thefreeul het.

the. power output of the engine drops; nun-e rnpiilly than the speed.Inolher wordsq the sanne results cannet he, olitninefi with e lie Selengine as ywith n gasoline lnu'iiing sng'ine, which will consume :iteuch explosion any amount ol' vfuel within the engine enpneitysubstantially without regardA tothe engine speed. This verymateriel'di'erenee relulers engines of the owlinnrv'Dienel typeunsuitable ,for uses Such :is the ilriing ol uuleniohiles, where :Lei'nsiileruhle power rnnge is required nt any engine. speed ne- Cordingto the rend conditions. lt is well known that Diesel enginesnreilillieult lo Sturt, the reason heinY 'l'eunil in the ferent ingdiscus-sien. lf nn engine is ileeigued when running; eolil or nt len'speed to give n pressure :ind temperature snilnhle fin' ellieienteinnlnistion. it `will he uiuleileeil hnl'. the prensures andlennnierainren will heneeellesily high `when this engine. runs nt. highnpeeil. Diesel type engines are i'heielere designed for one `zit-i011 uttheir normal snee@ and when operated below this speed, the conditionsare'lnot suitable and when startling,r an engine, it is necessary toturn it over many times before the pressure and temperature will bebuilt up to the point where combustion takes place spontaneously. rI'hisand the impossibility of hand-cranlringv a Diesel type engine arefurther reasons why it is unsatisfactory lor uses such as automobilepropulsion. I

The present invention provides a method of control, which vwill ensureat low speed pressures landv temperatures more nearly approaching thoseof high speed operation than has heretofore been possible. This meansthat an eng-ine may bev started with comparative ease and will deliverat low speeds considerable amounts ot power, because with the relativelyhigher pressures and temperatures at Alow s eed larger amounts/of fuelmay be burne at .each ex plosion and {reater power developed.

In the accompanying drawings which illustrate one form of apparatusconstruct-A ed to carry out the invention Fig. 1 is a fragmentary sideelevation of an engine oi the Diesel type.

Fig. 2 is a vertical sectional -view on the line 2-2, Figurel. I

Fig. 3 is en enlarged view partly 1n section of the air controllingmeans. Fig. 4 is a section on the line -i-/1-,Fig ure 3.

Fig. 5 is a fragmentary view similar' to Finire 1 illustrating amodification of cylin er construction.

Referring more particularly to the drawings, l1 designatesthe hase orcranlr case of an engine upon winch is mounted a plurality of vpowercylinders 12, 12th-'12. For each power cylinder there is provided apumping cylinder, these cylinders being respectively rdesignated 13,ISL-13" and being,r of greater volume than the power cylinders. Thepower cylinders and pumping cylinders may he in any suitable mechanicalrelation but `it is at 'present considered preferable to arrange eachpumping cylinder in axial alignment.v with-the power cylinder withwhichjt is associated, as clearly shown in the drawings. Thisarrangement enables considerable sinn'ililicalion in the. manufactureand provides a compact. arrangement and also other advantaa'es whichwill he hereafter pointed out. lilith the avial alignment ot the powerand pumping' cylinders, the pumpingr cylinder will preterahly he ofgreater diameter 'than the power cylinder, as indicated, so thatI the,ordinary type oi trunk piston 1-1 ol the power cylinders may operaiethrough the pumping cylinders and leave an annular Space of greatervolume than the, swept volume ot the power cylinders. rlfhe pistons l5of the pumpingV cylinders may be attachefhdirectly to or formedintegral' with the power pistons and he opcrated by the same connectingrods 1G, which under certain circumstances opemte the power pistons.Each pumping cylinder is provided with an inlet port 17 controlled by avalve 1S, which admits air trom any suitable source, such as a manifold18% The valves 18 may be ol'- any suit-able type, though at the presenttime revoluhle valves of the type shown are considered preferable. llachpower cylinder is provided adjacent its lower end with an exhaust port19, which may he bridged as desired. An exhaust valve 2O is providedclose to the port of cach cylinder. These valves may be oi? any suitabletype though at present the revoluble valve is considered preferable. Theair inlet and exhaust valves 2O ot the various cylinders may be arrangedin alignment and have a common operating means, as shown, but il othertypes of valve are used the same result may be obtained by appropriatemechanism. Each power cylinder is provided With an air inlet port 2lcontrolled by a valve.' In the form illustrated in Figures 1 and 2, theport is located at the top of the Cylinder and the valve is designated.9.2, while in the form shown in Figure 5 the inlet port is disposed atthe bottom of the cylinder with its upper end slightly below the upperend of the exhaust port 19, after the manner well known in theconstruction ot ordinary two-cycle gasoline engines. ln this latterdisposition ot' the port, the oiston 14 forms the valve controlling lowthrough the port. Each pumping cylinder 13 is connected by a passage orconduit 23 with one of the power cylinders. iV ith the arrangement ofcylinders illustrated, the connection is such that the pistons ofconnectcd pumping;r and power cylinders are working oppositely. so thatwhen the piston ot a pumpiuue' cylinder has completed its connircssionstroke, the piston ot the power cylinder in connection with this pumpingcylinder hasconipletcd its power stroke, as will be readily seen fromFigure 1. lt will he obvious that the connection of the pumping andpower cylinders depends upon the formation of the cranlr` shaft.

ln order to eil'ect the control ot air emission, as previously stated,the exhaiist valves 20 are provided with an adjustable drivingconnection in the enihmliment illustrated. lhis comprises a driving;rear 24 internally helically groovcd as at Q5. A helically toothedsleeve 2li is slidahly but irrevolubly mounted ou theI operating' sliatt2.7 of the valves Qtlandmaybe held in any position in the length ot' theshaithy suitable means such as a controlling,r lever QQ engaging in agroove Q9 oi theslecve. In .order to' secure proper relation in theoperation ol the valves 1S and Q0, the same may he driven from a coinamon source, tor example, by thenrrange- 'liti ment illustrated. rIhisarrangement comprises -a driving gear on one end of the series of valves18 and a small pinion 31 at the opposite end of the series meshing withand driving the pinion 24. lVith the design of engi-ne illustrated, theair valve 18 'isfrevolved at engine speed and the exhaust valve at halfengine speed, but it will be understood that with different forms ofIvalves or engines operating on diii'erent stroke-cycle' plans vthespeeds of valve Operation will :be altered.`

The operationo't' the device is as folcylinder 12s.

t0n 14;. of cylinder 12whieh is at the top ofy Assuming' the Vparts tohe in the position shown in Figure 1 and the crank shaft of the engineto be rotated, the pistons 14 and lare forced upwardly, the piston 15compressing any. air which is in the cylinder 13 through `the conduit 23leading to the power At the same time, the pisl its'strloke, descendsand, at the proper moment when substantially the Whole Volume ofthepower cylinderlQu is clear, the air riseSQio.a'point at which fuel willign-ite.

,. lOn' thealp. strokeof pistony in cylinder 12,

thel ompressor piston connected `to it also rises and compresses air fordelivery to the power Cyliiulrr 12. When the pressure andtemperature*iu`\.cylinder 12 have reached suitableilegrecs,"tliat is,when the piston is-fatk the top of its stroke, fuel is admitted;` in anysuitable manner and immediatelyignites, producing a very rapid eornbns--tion or explosion with consequent rapidI rise of temperature andpressure in the cylinder.

This presi-nrc exerts itself to drive the 'piston ldown until the portl!) is uncovered, whereupi'inl the fluid escapes,through the port. Atthc time the port uncovers, the `valve SBU'is positioned to permitescape of. thi` iras. 'lhisralve stays open until the piston roaches thecxtreme lower end of its stroke. The timing' of opening' of the port 'llis such that thc air from thc compressor cylimler admiitcil shortlyvafter' theI cxhaust port la() is uncovered. with the rc- 1suit that thefresh air ,which has been compressed in the conduit Q3 rushes into the,ypower cylinder and drives out the burnt gas.

If the valve 9.0 closes at exactly the time the piston reaches thebottom of its stroke,

such a quantity of air will be retained as is.

represented hy the full volume of the cylinder or nearly the wholeVolume of air delivered by the eompres'ssor will be retained in theengine ,cylindein As the cou'iprcssor cylinder has greater volume thanthe power cylinder, there may he therefore a slight siiper-atmospheriepressure in the power cylinder before compression by upward movement ofthe piston commences. If, on the other hand, the valve 2() rtunains openat least until the pover piston rises to cover the port 19, it will beapparent that some of the airadmitted will he displaced hy the pistonand forced out of the cylinder, so that compression will not commence atthe beginning 0fv the up stroke, with the result that a lower ultimatecompression pressure is obtained in the cylinder. Assuming for examplethat the volumes of the power land -compression cylinders are in theratio of 1:11.25 and that the depth of the port 19 is one-seventh thedepth ofthe cylinder and one-sixth the stroke of the piston, thefollowing);v extremes of pressure conditions will he obser\-'ed;-lViththe valve Q0 closing at the extreme end of the-piston stroke, theinitial pressure inthe cylinder will he '1.25 atmospheres, which oncoinpletiouof the stroke would represent a pressure of 8.75atmospheres,l (without. considering the increased pressuredue toincreased ten'ipcrature), Ifl; on the other hand the valve Qi) does notclose before the piston covers. the port 1S)7 there will be. an initialpressure in siX-seveuths. ofthe cylinder of 1.25 atmospheres, (withoutconsidcring` loss of pressure due` to equalization through the openvalve). will therefore be a pressure of only i atmospheres (withouteonsiilering the increase of pressure, due to increase ot temperature.)a matter of fact, if the valve 2li docs not close before the port lfl'iscovered by the piston, there will be a very substantial drop in theinitial pressure due to equalization through the open io'rt valve withAthe outside pressure. Inrea ity, the pressure at the completion` lof thestroke would' he only a little in,K excess ofsix. atmospheres. VIt willthus heseen that by regulating'the time of closi.n,ej of the` valve S20(the difference in pressure of approximately `1.15 atmospheres j willresult. ThenA the increase 1n pressure due to the increase intemperature arisii'ip; from conujiression is takeny into' account, itwillbe seexrtllat there will be avery .marked dilerence in.compressioinWhen au engine is being;-startedjcoldor,-1srun1ung at low speed. thereis a considerable,loss of coinpression heat. through the. @link-,ler"Walls,

.with a resulting,reduetionof pressure.

When an enginefgisrunning athigh speed., the cylinder' walls are much,wai-mer, owing On ICompletion of the stroke thcre sov iii

tio the more frequent, compressions enfleie illosions, nucl there muchless time during' euch eoiiipresfiing operation for .loss oi; lient, sothat., startingl witl nir Charges equinos to voluuie and pregfsyure, theresulting pressure when operating ab high speed is inneh lgreater thunthe resulting: pressui'ewhen op- [pressures unil teiniieiutiuresehtuineil upon .fill

comprension approach more nearly to the pieignitiou )Vu'ei-suies nulltemperatures ot high speed operation, in which e smaller quant-ity ot:iir is found ut theeou'niieneenient oi compression. This ineens thatwhen running at low Speeds or when' Sturtingy u eohl engine thevconditions npproneh those olitaining when'the e'iifegine running' :ithigh speed. Under these oonilitioneV7 the engine will start verv easilyund will operate nl, low Speeds with :veryv nearly the suine eiiieieneyas. :it high speeds.Il

The proportionately' higher pressures thusohininul'ile at low speed 1enables o linger innount of fuel .to he burnedlut low speed 'thun ispossible iiiiliesel type engines :is ordinarily eonetriioteil, with theresult that materially grenier power may he developed :it loiv oeil thanhee heretofore 'been possihle lhis eii'eet .imports to en engine uoeorrug to this invention 'ieihility'o't rontrol, :in it enelilee'the powerdelivered to he veritil indepenflf-intlyof the speed.. rlie engineshoulil ne (l'esifgnetl so that when. oneruiingf; with the ni'uiinuui.fiueniity of nir Sui-li adequate for 'the Combustion olf the inexiinuinqnuntity ofuel that nur he (leuienileil hy lood oonilitiona ilusuiningery unil the Sleeve 2G slidleneil'ifuiue on the vulve shaft. 27, itwiilhe oliserved thut, owingr to the .ielieul groove connection between thegroin.' :nui the sleeve Q6, the sleeve will he eoinpelleil to partiel-lyrotate, the [Iii-ee tion of roliriion dependinguponwhether the sleeve isiiiovei-l into or .out ot* the geur, ,alle the Sleeve is irrevolulilyoi'ineetml to the vulve she lit il?, it .follows that the vulve shuf;will receive ilie sinne -ifot-ntioii. llniler nervire roiulitions thegeur 2lluin pi'isitive ilriv ing' eonnertioii with the engine iriiiihiein: l., :is hure also ihn engine pistons.' lt there- 'loro l'ollou'sthat it the sleeve is yniovril either iii. or out, the relationorlliefi'ulves 2li to the p istoiis-uill ne ultereil. rlliis holils truewhen the engine if: ruiming', :is: the r1-enr Qlirnnnot ollei ils' speedrelation `with the eriiiilc shaft. The result; therefore is tliiit thevalves 2l) will .receive movement in :nl`

dition to that imported by the crank `slm-ift, so that they will. be Setuliearl of the crunk shaft or will receive motion oppor-ite to that l otthe e zink Shaft, so that, the;v will he Set' heel(` relatively to theCrank eliiift. Thisl lll setting ahead or heck of the vulves will 11e-,enity in their covering; nucl rncoverine` the ports l?) .in differentpieton positioiis, so f' that, the ports 19 will he Closed either whenthe piston is et the extreme.lower end ot' the-stroke or when it :ishalf covering; thi; ports or not until the ports ure eiiiireiv coveredby the piston. Any suitelile enil conveniently disposed iueniisi may hepio vided to operate ihis sleeve-'hut fri "n pine 3Qv ticaly point; ofview, it is :necessary that 'Fuel conditions are varied to reneehie-reuse in engine speed, the ineens for flete 'mining the quantity ofair available for eoihp Sion should he eorresiondingly or' autorMolly-ope sited to cause the quantity et oir available "no he deereiseeles the .speed nereuees and vice versn. '.lhe fonctionnel the valves 18nre olivionsly'to close theoWte l? and permit compression of :iii: "epistons l5. fis the pistons 15 have pegno@ anni unveriolole connectionwith 'tlieferiinlit shaft, it is not necessary tohave :my ecljneb nientfor the valves 18 :incl these may therei fore he directly and positivelydriven 'roin 95 the eravinlc 'shaft without any urljustu'ioniis..

lu fort, this iii highly desirable, es it ensures at erich stroke'tliedelivery oan ,ocoi'irntelv iiieesureil volume of air to u power Cylindersind lleuven all Jhe adjustment to he umile in lli the amount of airretained in the power oviirulei'. Obviously, the vnlvesi 18"1iiiigiul he:nljustuhle to regulate the ernennt, of nir rlruwn in hy the pistons l5'for Conuiressinn, hut this would introduce coijnplieutioiis unil mi) iti5 even possihle that the tvf'o adjustment-s niigglil. clusli in `thehands of :in ui'isliilleil, oi'iorutor. Flhe'size of ouch compressionsyl iiiiler will he proportionate to the size oii` lho power eyiinrlitito provide n Sullirien; "1 Superrlmrgo of air to folie eure ot theuin.\'iiiiuiii ilili'ereuee ol conditions 'for ivliielitlie engine isdesignen, Obviously, 'there nothing to Prevent `the valves. 18 heiligSeli lo close the ports 17 before the oudl in pince lill .ot :it theonli ot' the, suction sti-ohh. so that ihe compressioncylinders muy niiie per-- ,iuiineut delivery ot nir heloiv their niixiiinon capacity. i

is previously stated., the nir inlet ports of the cylinders nre notuncovereil until tho pitonii have uncovered the efzlinunt ports. l).lhisiis obviously"neeesisury' mi, if the Viiir )erts opened hetero theexhaust ports, the l lun-nl: charges in the efilinilersi nouhl lionv "1lhroiinh the nir ports in piuceo'if thhgiifngh the exhaust ports. Thetime olf uucovelii ol the uir ports is therefore set relatively to theuncovering' of the ertheust glorie, in Such :i nimmer us lo ensure thatgue rireueuro iniv lthe "o yliiidei'i'A will be .below the pressure oftthe ii'iooi'ning air. kThis' is effected' by .fii'opei' .setting.oftheinechanism operziting ot ignition tei'npei'ature olicompression`at 4'minimum engine spoed-and releasing in stirb-f.

thevalves22 Whe'ii'siioti are used or by the" l "proper positioning ofthe poifts 21 when they pistons 'n s in Fi'giire Iii-either crise the:`-iiicoiniiigif :iiiserves to drive o-iit.tlie"biirnt gzisesjaud. effectn ,thoi'oiigh scavengingor 410v cleaning-'ot the-"cylindersi #It-fis tobe eie Footed .that a; small. iinoii'nt ofxairwill 'be `ost Vin thisscavenging .operation but l this is token'into' consiefatinfinfixing'the rein-' the poweip and froo'inpiessioii cylinders hzts...beengilinstiated is en iiiizing'e mentotpi ing,itWillibeundei'stood that this is'pure)iii-metterei design." r

A0 'Having thus described'myfinyenltioii?what.

f l' c1ai`mis:-.

sion enginestooperntezit varying speeols consisting" 11i-.adjusting .thevolume oi-4 air-- g5 ,ooinpiiessedfin such inverse t'ratio tothe rate ofoinpi'ession fisio maintain coiistantignition vtei'npertiture's"iiiespeotive of variations' i of jengine'speed.

:2. A. .method of 'regulating iiigii "Cem-plee .SUSion engines togoperate at viyin'g'sp'eeds .fooiisisti'ig "inl -adjusting the volume' ofnir,

" oompressedinsiioh inverse riitioto the rate otfoonipi-ession iis tomintain constant-igni-`V j tion temperatures irrespective of variations5 'ofeiigine speed throughout a Wide range 'oij' engine speeds.'

tigri method ofjreguiatiiig high coi'iipres.- sion engines-gto operateat v iirying speeds "vconsistinglr .in delivering' :i deiiii'itefchai'ge40 of xiii' tothe Working cylinder :init i'egiilatf. ing-'the proportionlof the `charge retiiineds for compression. in. such 'inverse ratio to,the

consisting in delivering a denite charge of air to-tlieyvoiking cylinderand iegiiiating .o'ftho pijoportionj of the' ohige retained' for.

ooi'npressioninjsueii inverseiato'to the rate of 'compression nettf-,maintain ignition temperatures 'constant 1i'i'espenti-ve of tengine us. 5. A method- 0iiguiatmg'iiigii,compres sionengi'iiestoppeizite @it vnryip] speeds -consisting ofinieoting 1ntlioinil'gizt 7iA h'ile. the'` connection betwe'eii' they compression.'cyiindersand the .engine l 'cope of the air from the cylin cycle si i'siipejtrnospheioolio-rg0 of nii' iiidoipi'ioi' to` compression for'vdevelopment sequent cycles a portion. ofthe s iipe'iatmos- '-phei'iccl'iarge of ali-rin the Working oy1i-iideiin 4s iioh iiiverseiatio toengine speedesto maintain constant' ignition @temperaturesf (i. methodof iegn'ziting high compresf Speeds working foyiindeig compressingappone I in ateiy the entire air.. charge ntlririimumciiii'itgeretained. for'Coiiipi-:ession when. the

speedfii'ieieiisesv and in siicii inverse ratio vtoV the speed increaseiis to maintzina'pproxif Vinfiteiy constant pre-compression pressures.nndv temperatures. for all cycles ,of operation irrespective. of 'speedV"vaiiations'- pression eng widely varying-speeds, consisting injoliiirging theworking c yi'indei7 for each cycle of j operationy with:i [volume oir v:iir 'greate'irfzit atrnos keria-pressure .tian' the4volume of .theoy i nder compressing, approiniately the. -full a'ir'charge aitminimum .speeds ofrot'ef -tioi'lvandreducing thequntityfdf airooin' pressedv for increased speeds midst() efdegiee so proportionedwith ieSpeQttotiie Speed' 4"in'rense' .as to. maintainv approximatelycon! .stiint pieJeom 'ressioii pressure and 'tenif peinture'-`conditions. irrespectiveof enginespeeds. v 8. A.

sisting in oh'nrg'ing afwerking -eyiindeig for eiieh cycle. ofoperation, with a voi-lime 'o aii greater at -atmos herio inetho'd'o o'eij'tiiig high compres. `sion' engines' 4:it wide y.' varyingv speeds,Aoonv pressure. than -f the volume of the cy inderan'd reiiiatinfgfescompression sind in -su'ohl ireet'retio 'with .respect to'. variations-ofengine speedthatasx the speed ofthe engine Vai-iesvth'equantity vofair retained for compression is'geiso ve.-

irrespective fof engine speed,

In vWitness whereof, I eve :my hand".

er prior to- :los

